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21.
K Uchida Y Miyauchi H Nakayama N Goto 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(3):605-611
Amyloid angiopathy with cerebral hemorrhage and senile plaques was found in the brain of aged dogs. In all 9 cases examined, 13 to 19 years old, 6 males and 3 females, amyloid deposits were observed mostly in the wall of cerebral arterioles and capillaries showed hyaline degeneration. The accumulation of amyloid fibrils measuring about 10 nm in diameter was seen in the cerebral vessel wall by electron microscopy. The cerebral hemorrhage was observed in 6 of 9 dogs and 2 of them showed massive hemorrhage. The hemorrhagic foci were sometimes closely contact with the vessels involved in amyloid angiopathy. In addition, senile plaques being classified into 2 types were found in the cerebral cortex of 3 dogs. The first type was characterized by the accumulation of degenerative neurites and often contained granular argyrophilic material. The second type had a well-defined amyloid core with neuritic halo. Amyloid deposits were also found in or around intestinal vessel walls of 3 dogs. The amyloid deposited in the cerebral vessels, senile plaques and intestinal vessels showed characteristic green birefringence under the polarized light even after potassium permanganate treatment. 相似文献
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Tadahisa MASHITA Hiroaki KAMISHINA Yuya NAKAMOTO Yosuke AKAGI Ataru NAKANISHI Yusuke HARASAKI Tsuyoshi OZAWA Takashi UEMURA Yui KOBATAKE Shunsuke SHIMAMURA Naoki KITAMURA Sadatoshi MAEDA Yuji UZUKA Gerry SHAW Jun YASUDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(4):433-438
The aim of this study was to evaluate the prognostic value of concurrent measurement of
serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary
T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent
measurement of these would provide a more accurate prediction of functional outcome in
dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control
clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The
association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2),
deep pain perception and surgical outcome were evaluated with logistic regression analysis
after three months for all 94 surgically treated dogs. Sensitivity to predict
non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both.
Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were
significantly correlated with surgical outcome (P<0.05); however, deep
pain perception was not (P=0.41). The results of logistic regression
analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for
serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity
and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6
ng/ml, using T2H/L2 value of>0.84 and using both
serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%,
respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful
for predicting long-term outcome in dogs with thoracolumbar IVDH. 相似文献
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本研究从甘薯种植地、淀粉厂厂区及下水道等有机质丰富的地方采取土样,从中分离产糖化酶细菌.其中一株命名为S3的分离菌株,根据形态特征观察、生理生化性状检测、全细胞脂肪酸成分分析、16S rDNA序列分析DNA-DNA杂交等鉴定实验结果表明属于类芽孢杆菌属(Paenibacillus).根据16S rDNA序列构建的系统发育树,与S3进化距离相近的类芽孢杆菌菌种分别为:P.curdlanolyticus、P.kobensis和Paenibacillus sp.PALXIL08.但是,S3菌株在生理生化特征及细胞脂肪酸成分含量等都与这3种菌有所不同;DNA-DNA杂交实验表明S3和这3种菌的同源性分别为37.8%、21.7%和29.4%.因此,S3菌株可能是类芽孢杆菌的一个新种. 相似文献
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Noboru KUDO Chieko OTA Fumiko SAKA Yae IKEDA Yusuke TOMIHISA Yasunaga ITOI Takashi OYAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(12):1651-1654
Seven laboratory mammal and
bird species were orally inoculated with 200–1,000 encysted Metagonimus
hakubaensis metacercariae that had been isolated from naturally infected
lampreys (Lethenteron reissneri) captured in Aomori Prefecture. At 8 and
15 days post-infection, adult flukes were recovered from all of the laboratory animals
tested, and therefore, hamster, rat, mouse, dog, cat, chicken and quail were considered as
final hosts of M. hakubaensis. Recovery rates of the fluke were higher in
dogs and hamsters than in cats, rats, mice, chickens and quails. The flukes recovered from
dogs and hamsters showed increased body length and higher fecundity than those recovered
from the other hosts. These results indicate that the suitability of dogs and hamsters for
M. hakubaensis infection is higher than that of the other laboratory
animals. 相似文献
29.
The primary function of the placenta is to act as an interface between the dam and fetus. The anatomic structure of the chorioallantoic placenta in eutherian mammals varies between different animal species. The placental types in eutherian mammals are classified from various standpoints based on the gross shape, the histological structure of the materno-fetal interface, the type of materno-fetal interdigitation, etc. Particularly, the histological structure is generally considered one of the most useful and instructive classifications for functionally describing placental type. In this system, three main types are recognized according to the cell layers comprising the interhemal area: (1) epitheliochorial type (horses, pigs and ruminants), (2) endotheliochorial type (carnivores) and (3) hemochorial type (primates, rodents and rabbits). The number of cell layers in the interhemal area is considered to modify the transfer of nutrients between maternal and fetal blood and is one of the important factors with respect to the difference in placental permeability between animal species. Therefore, in reproductive and developmental toxicity studies, careful attention should be paid to the histological structure of the interhemal area when extrapolating information concerning placental transfer characteristics to different animal species. 相似文献
30.
Satoshi HARA Takashi TAKANO Mio OGATA Reina YAMAKAMI Yusuke SATO Tomohiro KONO Yayoi OBATA 《The Journal of reproduction and development》2014,60(3):250-255
Transgenic mice are essential research tools in developmental biology studies. The 2A peptide allows multiple genes to be
expressed simultaneously at comparable levels in somatic cells, but there are no reports of it being used successfully in
germ cells. We constructed a Cre/loxP-based conditional vector containing the 2A peptide to significantly enhance the
expression of a reporter and target gene from a constitutive promoter in oocytes. Mice with a transgene insertion containing
the chicken β-actin promoter, floxed EGFP-polyA cassette, mCherry reporter, 2A peptide and target gene DNA methyltransferase
3A2 (Dnmt3a2) were crossed with TNAP- or Vasa-Cre mice to produce offspring, in which mCherry and DNMT3A2
proteins were highly expressed in oocytes upon Cre-mediated removal of EGFP-polyA. This novel transgenic mouse line based on
the 2A expression system can serve as a useful tool for examining gene function during oogenesis. 相似文献